We were just at Hershey a few weeks ago. There are tons of rides for younger kids and they'll allow you to bring some snacks in with you so we avoid buying as much food that way. Their food prices are REALLY high as someone said.
A little tip--you can get discounted tickets for Hershey Park at Giant grocery stores. They are all over PA. I will say that even with the discounted tickets, for the three of us (myself, DH, and DS(4) ), the bill was still 108.00. Without the discount, I believe it would have been closer to 130.00. Also, if you buy a souvenir cup at HP, they will fill it up with water for free all day long.
We've also done Lancaster though not Dutch Wonderland. Our son got a kick out of buying root beer and pretzels from Amish children. Bird in Hand is a nice little town in Lancaster that has a farmer's market and is easy to walk through. The Strasburg railroad is also nice and if you check, Thomas the Tank may be there.
Wow. I didn't mean to write this much, LOL.